The invention relates to a rope brake, especially a brake for synthetic fiber ropes such as climbing ropes or the like.
A rope brake of the above kind is disclosed in German utility model registration 89 04030.9. The housing of this known rope brake comprises essentially two guide webs mounted parallel to each other. The guide webs are rigidly connected to each other and have slots which are mutually coincident. The action of this known arrangement as a rope brake is achieved in that a spring hook is hooked into the two longitudinal slots and a rope loop is placed about the transverse member of the spring hook which extends through the slots. When a load is applied to the rope, the spring hook is displaced within the guide slots in such a manner that the rope loop is clamped between the transverse pin of the spring hook and a transverse pin between the guide webs. The manipulation of a rope brake of this kind is difficult and leads to a time costly physical effort when stiffer and/or thicker ropes are used. Furthermore, the braking action occurs only with use of two separate parts which must be assembled first in a correct manner by the user.
It is an object of the invention to provide a rope brake which is easy to manipulate and which provides a wide area of application and a high level of security and safety. The application is intended for the area of climbing sports to make possible the safety of persons climbing ahead and climbing after as well as the use as a rope-down apparatus and as a rope clamp. The application in both cases is for a simple rope as well as with a double rope.
The rope brake of the invention is for a rope including a climbing rope made of synthetic fiber. The rope brake includes: a housing; a guide arrangement for applying a braking action to the rope and the guide arrangement being disposed on the housing; the guide arrangement including at least one opening formed in the housing for passing a loop of the rope therethrough with the loop defining a plane; and, a pin extending across the opening and extending though the loop so as to be grasped thereby; and, the pin being mounted on the housing so as to be movable in the plane.
With the invention, one obtains a light, self-blocking apparatus which requires no additional parts, such as additional spring hooks. The manipulation is simple for all applications and the safety is high especially because a rope, which is guided in the brake, is automatically clamped tight under an adequately strong load or for a slight pull on the brake rope so that, to secure the load, no holding force is required. The insertion of the rope as well as its loosening can be carried out after a loading without difficulties.
It has been proven useful to configure the opening in the housing as a slot. It is especially advantageous when two openings are arranged for the passthrough of two rope loops one next to the other and the braking pin spans the two openings from the top. However, in lieu of two separate openings, a wider opening can be provided which corresponds to the total thickness of the two ropes or a single opening corresponding to the thickness of the used rope when the brake is designed for only one rope.
The braking action of the rope brake arises in a very simple manner in that the pin, which spans the opening or openings, is displaceable in the direction of the opening in the housing or in the plane defined by the rope loop, so that, under load, the rope loop is clamped between the pin and the housing. The insertion of the rope is especially easy because of a simultaneously pivotable arrangement of the pin.
As long as the rope is not under load, that is, with rope feed and with rope payout, the pin is secured by a spring and a latch against pivoting, preferably by a spring and additional ribs on the housing or by a spring element and a stop of a guide element connected to the brake pin. This stop is advantageously provided on a bearing block in which the guide element of the pin is held longitudinally displaceable as well as pivotably. The same spring furthermore effects that the pin during rope feed or payout is held in its neutral position wherein the rope is free of clamping and can slide in the opening. The guide element can, in addition, be displaceable in its longitudinal direction and therefore also in the displacement direction of the brake pin so that the unloaded position of the pin or the adjustment path for braking is adjustable by clamping the rope.
An attachment device is provided on the housing for attaching a body, which is to be braked, to the rope brake when roping down or for attaching the rope brake to the person operating the rope brake or in the area of the person. This attachment device comprises, for example, an attachment pin between two lateral webs on the housing of the rope brake in combination with a band loop which makes the use of an additional spring hook unnecessary or of an attachment opening directly in a housing wall. In lieu of a band loop, a spring hook can be hooked directly into the attachment device. In lieu of the attachment pin between two lateral webs on the housing, it can be advantageous to provide a single center web on the housing with one or several cutouts for looping in the rope loop or a spring hook. The cutouts are arranged in different positions to the opening(s) for the rope passthrough. The braking force is determined by the position of the attachment device or the attachment opening relative to the displacement direction of the brake pin. The closer the attachment point comes to the displacement direction of the brake pin, the greater is the braking force of the rope brake of the invention. For this purpose, several attachment possibilities, which can be used selectively, are provided. In lieu of separate attachment points, it would, however, for example, also be possible to guide the attachment device in a slot against the force of a spring so that the brake force changes in dependence upon the spring force or the spring pretensioning and therefore in dependence upon the position of the attachment device which results.
It has been shown especially advantageous in practice, when at least one additional cutout for additional guidance and/or reversal of a simple or double rope is provided which is preferably configured to be open and serves for the guidance and/or reversal of the brake rope.
For limiting the brake force to protect against overloading, damage or injury, it has been further shown to be advantageous when at least one stop for the pin is provided on the housing which limits the movement of the pin in the direction of movement of the pin which occurs during loading of the rope, before reaching its possible end position. This end position is caused by the deformability of the rope.
In a constructive context, it has been shown advantageous when the spring is mounted covered in the housing and preferably in a blind hole arrangement in the actuating lever. In this way, one obtains a rope brake which is improved with respect to its operational safety, manipulability and resistance to disturbance. Damage or operational disturbance of the spring, which coacts with the brake pin, is substantially precluded.